1. Field of the Invention
The present invention relates to a display device which uses a touch panel as an input device.
2. Discussion of the Background
In recent years, transparent touch panels that allow a user to provide input by simply touching a display screen with his/her finger or pressing it by a pen have become widely used. Such touch panels use a transparent conductive film as an electrode which is generally made up of a glass or polymer film and a conductive film laminated thereon. Recently, a polymer film such as polyethylene terephthalate is used for the transparent conductive film due to its high flexibility and workability, and light weight.
During the manufacturing process of the touch panel, the transparent conductive film is patterned to form a portion having a transparent conductive layer and a portion not having a transparent conductive layer, thereby providing an electrode wiring of the touch panel. This pattern is required, as a property of the transparent conductive film, not to be easily seen by visual observation.
In order to provide a pattern with invisibility for the transparent conductive film, an optical adjustment layer having high refractive index is typically disposed between the transparent conductive layer and the substrate.